There are only seven Web sites that more people use than Wikipedia, the online encyclopedia that lets anyone edit most of its articles. None of the sites that are more popular than Wikipedia have as their main purpose producing information about the world. The top sites, Google and Yahoo, mainly function as links to other sites. Facebook and Myspace, which people use to keep in touch with their friends, are third and fifth most popular, respectively. The other sites that are more visited than Wikipedia are YouTube (a kind of online TV), eBay (a virtual flea market), and Microsoft's version of Google.

For high school and college students researching their papers, Wikipedia is indisputably source number one.

Wikipedia was founded in 2001. It now has 16 employees. For such a young and small organization, it has made its share of headlines. The New York Times covered the story when Wal-Mart employees were found to have anonymously modified Wikipedia's article on Wal-Mart's labor practices, and ExxonMobil employees were caught anonymously changing the section on their company's disastrous oil spill in Valdez, Alaska. None of these editors disclosed who they worked for; a grad student created a program that ferreted out the names of the companies that owned the computers used to make the changes. More recently, one of Wikipedia's board members was criticized for freezing the site's article about his girlfriend, a conservative Fox TV commentator.

While Wikipedia lets anyone edit most of its articles, some can only be modified by Wikipedia staff. It is often hard or impossible to find out the identity of the people who wrote and/or modified an article.

It's likely that any college student who was assigned to write a research paper on nuclear power would do a Google search for those two words. A person who recently moved to an area near a nuclear power plant might do the same thing. The first result is Wikipedia's article on the subject. The article's introduction is locked, so only Wikipedia staff can edit it.

Printed out, Wikipedia's "Nuclear Power" article runs to about 20 pages. It serves as a good example of the famous Web site's flaws.

Nuclear power provides almost a fifth of the nation's electricity. The industry's two biggest problems are what to do with nuclear waste and the risk of a Chernobyl type accident.

Wikipedia bends over backwards to downplay these problems. And it fails to mention that there are much cheaper, safer and more environmentally friendly alternatives to nuclear power. The article also fails to mention the taxpayer subsidies that created the nuclear power industry in the 1950s and 1960s, that allowed the industry to grow and that keep it alive today.

The Atomic Energy Act of 1954 effectively created the nuclear power industry. The government provided the industry with millions of dollars of free research, heavily subsidized fuel, discounted waste disposal, tax breaks, and, perhaps most significantly, taxpayer-subsidized insurance in case of an accident. The insurance was provided by the Price Anderson Act of 1957. Congress has renewed the act approximately once every 10 years, and it's still in effect.

Between 1974 and 2005, the federal government spent (in 2005 dollars) on research and development $48 billion on nuclear power, $20 billion on fossil fuels, $12 billion for renewable energy like wind and solar, and $12 billion on energy efficiency.

A 1982 study performed by the federal Nuclear Regulatory Commission for Congress predicted that a serious accident at the Indian Point nuclear power plant near New York City would kill 50,000 people and result in 100,000 "radiation injuries" and $300 billion in property damage. This study has never been updated. The Wikipedia article "Nuclear Power" does not mention it.

Former federal prosecutor Kenneth McCallion wrote in his 1995 book, "Shoreham and the Rise and Fall of the Nuclear Power Industry" that "James Asselstine, a former member of the Nuclear Regulatory Commission, has concluded that there is at least a 45 percent chance of a meltdown of a nuclear reactor somewhere in the United States in the next 20 years."

If a plane hit the so-called "spent fuel pool" (the water-filled nuclear waste storage area) at a nuclear power plant, a catastrophic nuclear emergency could ensue, according to a 2004 report by the National Academies of Science. On Sept. 11, 2001 one of the planes that hit the World Trade Center had minutes earlier flown almost directly above the Indian Point plant.

The accident at the Chernobyl nuclear power plant in the Soviet Union in 1986 has killed or will kill (by cancer) an estimated 9,000 people, according to a United Nations report. The Wikipedia article wrongly puts the number at 4,050.

President Jimmy Carter's Department of Energy agreed in 1977 to take all the industry's "high-level" nuclear waste. It wasn't until 1987 that Congress decided where the federal government would dump the nuclear waste that Carter had offered to take: Yucca Mountain in Nevada.

The nuclear waste dump at Yucca Mountain still has not opened. The U.S. Department of Energy estimated in 2001 that the total cost of the dump would be about $58 billion. The waste is still being stored around the nation near the 103 reactors where it's created.

In 1995 the National Academies of Science issued a report that said nuclear waste kept at Yucca could still be deadly in 1 million years. The waste needs to be protected by armed guards around the clock.

The Wikipedia article repeats a claim that the industry has been making with no evidence for the past 60 years: "The current waste may well become a valuable resource in the future."

Spending one dollar on energy efficiency programs like Efficiency Vermont saves approximately three times as much energy as spending one dollar on nuclear power generates. That's according to a 2005 study by Amory Lovins in the journal Nuclear Engineering International. The dollar spent on energy efficiency also creates more jobs than the dollar spent on nuclear.

In other words, if Americans took the money they now give to corporations like Entergy Nuclear for electricity from nuclear power plants and instead spent it on programs like Efficiency Vermont, the nation's 65 nuclear plants could be closed, electricity bills would go down, and there would be a net increase in jobs.

Wind power is cheaper than nuclear power. Wind power and energy-efficiency programs are at least twice as cost-effective as nuclear power at reducing greenhouse gas emissions. That's because of the fossil fuel emissions caused by construction of nuclear power plants, mining and transporting nuclear fuel, and transporting, guarding and storing nuclear waste. Nuclear power causes global warming.

On May 2, 1977, police arrested 1,414 protesters at the Seabrook nuclear power plant in New Hampshire. In June 1978, some 12,000 people attended a protest at Seabrook. In August 1978, almost 500 people were arrested for protesting at the Diablo Canyon nuclear power plant in California. In May 1979, in Washington, D.C., about 70,000 people, including the governor of California, attended a march and rally against nuclear power. On June 2, 1979, about 500 people were arrested for protesting construction of the Black Fox nuclear power plant in Oklahoma. The next day, 15,000 people attended a rally at the Shoreham nuclear power plant on Long Island, N.Y.; about 600 were arrested. On June 30, 1979, about 38,000 people attended a protest rally at Diablo Canyon. On August 23, 1979, in New York City about 200,000 people attended a rally against nuclear power. On September 23, 1979, about 167 protesters were arrested at Vermont Yankee. On June 22, 1980, about 15,000 people attended a protest near the San Onofre nuclear power plant in California.

No new nuclear power plants have been ordered in the U.S. since 1978.

Protests preceded the shutdown of the Shoreham, Yankee Atomic, Millstone I, Rancho Seco, and Maine Yankee nuclear power plants. A 2007 article in the Journal of American History did not hesitate to give protesters credit for the decline of the nuclear power industry: "The protestors lost their battle [when Diablo Canyon opened in 1984], but in a sense they won the larger war, for nuclear plant construction ended across the country in 1986."

The Wikipedia article says, "[P]olitical resistance to nuclear power has only ever been successful in New Zealand, and parts of Europe and the Philippines."